This invention relates to inkjet printing mechanisms, and more particularly, to a separable key device for establishing detachable printer component compatibility with a printer.
An ink-jet printer produces images and text on a page by firing drops of ink from the printheads of one or more ink cartridges while the cartridges move back and forth across the page. Examples of ink-jet printers include plotters, facsimile machines, and typical computer-attached ink-jet printers. The page on which a printer prints may be any sheet of material, such as paper, Mylar, foils, transparencies, card stock, etc.
The ink supply of an ink-jet printer is limited. Thus, many cartridges are designed to be detachably secured and replaceable. A user simply replaces the old, empty ink cartridge with a new, full ink cartridge. In these so-called cartridge-type printers, the cartridges can be manufactured as a unit that includes a printhead and an ink reservoir (referred to as an xe2x80x9cink/printhead cartridgexe2x80x9d herein). Thus, these types of ink/printhead cartridges are seated in a carriage that travels back and forth across the page during printing operation.
Alternatively, in some designs commonly known as off-axis printers, the ink reservoir is a container that may be disconnected from the printhead, which remains installed on the carriage while the container is replaced. In the typical off-axis printer, only a printhead moves across the page, while the ink reservoir is stationary and secured to the base of the printer. Ink is delivered to an inlet port in the printhead via a flexible, ink delivery tube that extends from the stationary ink reservoir. Typically, the ink reservoir is mounted to the printer chassis and may be replaced or refilled when empty. Off-axis printers may be equipped either with a single printhead for monochromatic printing, or with several printheads for color printing. Of course, for color printing, several reservoirs and associated tubes are required, with one set used for each color.
In the ink-delivery systems of off-axis printers, the ink-delivery tube may be permanently connected to the printhead, but this would prevent replacement of the printhead. The printhead may suffer mechanical breakdown or simply wear-out after firing millions of drops of ink. Therefore, the printheads of a typical ink-jet printer are designed to be replaced, as necessary. Similarly, the supply of ink in reservoirs or containers used in cartridge-type or off-axis type printers may be replenished in refill stations that are peripheral components of the printer system.
Irrespective of the nature of the removable ink-jet printer component (ink cartridge, reservoir or printhead, for example), it is desirable to ensure that those components are accurately connected in the printer. That is, a component such as an ink/printhead cartridge must be properly seated in the carriage. Also, in instances where a carriage is designed to carry more than one ink/printhead cartridge, it is important that an ink/printhead cartridge having the correct print characteristic, such as ink color, be installed in the proper position in the carriage, so that the printer controller can precisely control the printing of drops of that color.
This proper seating and positioning requirement also applies to off-axis printers, especially where several reservoirs and associated ink-delivery tubes are involved.
In the past, various mechanical latches, datum features, and/or electrical identification techniques have been employed for ensuring that a replaceable printer component, such as an ink/printhead cartridge, ink reservoir, or printhead, is operably installed in the correct location in the printer. For example, the replaceable printer component may include a unique pattern of tabs associated with that particular component, thereby defining a key that is operably engaged with corresponding mating slots in the base on the printer to which that component is properly installed. The mating slots are typically integrally molded into the base, and they preclude a printer component that has a different pattern of tabs from being inserted into that particular base.
The working components of the printer, such as the carriage assembly and the like are often common components among a family of printers sold by a manufacturer. For example, a manufacturer may sell two similar printers, one having the ability to print in color and a virtually identical model, but that only prints in black and white. Similarly, a manufacturer may offer a variety of printer qualities, which necessarily require improved printheads and higher quality of ink in some models.
Despite the improvements of these known devices that ensure a correct printer component is inserted into a correct corresponding base on the printer, they offer several drawbacks. For example, all of these different printers in the family of related printers typically have the same carriage assembly, and related operating mechanical and electrical components. However, in order for a manufacturer to use these common components in such similar printers while still providing a key system to ensure only proper printer components are installed in the correct locations, each configuration of the family of printers requires a unique base having a different integrally molded pattern of slots. Manufacturing such individual base components necessarily increases the cost of production and related inventory management of these unique components. Also, the shape and angles of the molded key components necessarily increase the complexity, and therefore the related expense of the molds.
Moreover, should the manufacture, customer, or service technician ever wish to change the configuration of a printer, say for example, to convert a black and white printer into a color printer, or upgrade a printer with improved components, the old base assemblies having the old printer component key patterns must be replaced with new base assemblies having the new printer component key patterns. In practice, these bases are operably engaged with many related components, and their removal and replacement is difficult and time consuming.
Accordingly, despite the available improvements offered by traditional removable printer cartridge key devices to ensure that a proper cartridge is inserted into a proper base, there remains a need for an economical, easy to manufacturer, and easy to install key device that is unique for a particular printer configuration, but also allows a common cartridge base to be used for a plurality of printer configurations. In addition to other benefits that will become apparent in the following disclosure, the present invention fulfills these needs.
The present invention is a separable key element having a unique pattern of slots to receive a particular printer cartridge. The key element is operably secured to the component base assembly during assembly of the printer. The base assembly is common to all printers in a family of printers.
In a preferred embodiment, the key element includes a component base-mounting slot for operably engaging a substantially planar wall of the base, and the wall and slot have a unique mating key pattern, thereby preventing an improper key element from being installed into an incorrect location on the base.
Similarly, each key element also preferably includes a label tab for securing an appropriate identifying label thereon. The label tab assists the component installer by informing the installer which particular component belongs in that particular base. More preferably, the label tab is a unique shape that only conforms with the shape of the correct label to be inserted thereon, thereby reducing the likelihood of an improper label being inserted on the label tab during manufacturing.